import java.awt.*;
import java.io.*;

public class Rectangles
{
  
  public static void main (String[] args)
  {
    
    
    
    try 
    {
      FileReader in = new FileReader ("DATA2.txt");
      BufferedReader readFile = new BufferedReader (in);
      
      FileWriter out = new FileWriter ("OUT2.txt");
      BufferedWriter writeFile = new BufferedWriter (out);
      
      String line;
      
      while ((line = readFile.readLine()) != null ) 
      {
        int num = Integer.parseInt(line);
        
        int m = 0;
        int x = 0;
        int counter = 0;
        int rect; 
        
        do 
        {
          m = m + 1;
          
          do
          {
            x = x + 1;
            rect = m * x;
            if (rect <= num)
            {
            counter = counter + 1;
            }
            
          }while (rect < num);
          
        }while (m < num);
       
        writeFile.write(Integer.toString(counter));
        writeFile.newLine();
      }
      
      
      
      // Close the input file
      readFile.close();
      in.close();
      
      // Close the output file
      writeFile.close();
      out.close();
    }
    catch (FileNotFoundException e)
    {
      System.out.println("File does not exist or could not be found.");
      System.out.println("FileNotFoundException: " + e.getMessage());
    } 
    catch (IOException e) 
    {
      System.out.println("Problem reading file.");
      System.out.println("IOException: " + e.getMessage());
    }
  } // main method
} // class